Heat insulation



June 6, 1939. E. GOULD V HEAT INSULATION Filed Jan. 50, 1934 5 Sheets-Sheet 1 r II l June 6, 1939. R. E. GOULD 2,161,037

HEAT INSULATION Filed Jan. 30, 1934 3 Sheets-Sheet 2 June 6, 1939. R. E. GOULD 2,161,037

HEAT INSULATION Filed Jan. 30, 1934 5 Sheets-Sheet 3 Patented June 6, 1939 v UNITED STATES PATENT OFFICE near INSULATION Richard E. Gould, Dayton, Ohio, assignor to General Motors Corporation, Dayton, Ohio, a corporation of Delaware Application January 30, 1934, Serial No. 708,957 6 Claims. (Cl. 154-45) This invention relates to refrigerating apparathrough a refrigerator cabinet showing a modifiedtus and more particularly to heat insulated form of my inveh n;

cabinet constructions. Fig. 4 is a perspective view of one of the insu- It has been found that sheets of a metallic heat lating units shown within the walls of the cabinet 5 reflecting material, such as bright aluminum foil, f l 5 spaced by thin substantially dead air spaces, pro- Fig. 5 is a modified form of insulation unit for vides a very eflicient form of insulation. Howthe ab shown in ever, the fabrication ,of such. an insulation is a g. 6 is a sectional view along the line 6-6 of particularly troublesome problem. This is very a l0 important because of the fact that this type of Fig. 7 is a sectional view along the line '|'I 0f 0 insulationis in competition with other types of insulation, such as that of cellulose fiber loosely 818 a sectional view a o g t e l ne 8 o packed in a container, which are also relatively I high in efficiency and low in price. In order to 9 is a sectional View al n line meet this competition, it is necessary that this d foil insulation be either more efllcient or lower i 10 s a s ct View f another flin cost or both more efllcient and lower incest l ri l a Y than conipetjtive types Referring to the drawings and more particu- It is an object of my invention to provide an larly to there is S W a compressor 20 insulating structure embodying sheets of t for compressing the refrigerant and for forwardreflecting material, such as bright aluminum foil, 8 the compressed refrigerant to a condense! provided it th b t ti dead air spaces where the compressed refrigerant is liquefied and betwe th h t which is t least as emcient collected in a receiver 22. The liquid refrigerant and which can be readily and economically manuis forwarded through a pp y conduit 23 to a 25 factured at a rapid rate and at a lower cost than Suitable expansion controlling device, Such as a '25 other types 1 commercial i t restrictor 24, from which the refrigerant is con- It i a furth r object of my invention to p ducted through aconduit 25. to an evaporator 25' vide an insulating structure containing spaced located Within the f d compartment 21 of a, resheets and having a more emcient and more frigerator cabinet 28. The liquid refrigerant economical means for supporting the sheets which evaporates Within h evaporatolf 25 under 30 includes rather heavy paper strips for d into duced pressure and-ls returned to the compressor generally tubular structures extending parallel through the return conduit The compressor with th m of t sheets is driven by an electric motor 3ll under the con-'- It is another object of my invention to form a of a Snap acting Swltch h r wh light weight insulating structure including spaced Operated by a thermostat 32 m Contact mm t parallel sheets with substantially dead air spaces h f h the evaporator 26 and exposed 3 the therebetween which sheets are supported by a a wlthm the food compartmeht'fl' light weight resilient framework which may be The food h h h 27 is provided ,wlth cgmpressed to a varying degre to vary the spam sheet metal inner wall or inner liner 33 which has mg of the sheets and the thickness of the insulatits from edge hastened and sealed to rectangula'h 40 mg structure without material damage. h whlch suhmuhds h door opening- ,Further objects and advantages of the present wlthm the door qpemng .there 15 provided a suit invention will be apparent from the following able'door havmg an pan 35 formed of description, reference being had tothe accom sheet metal fastened to a framework of treated panying drawings, wherein a preferred formoof v heat conductivity. Fastened to this framework a ZZ P clearly shown 31 but separated fromthe inner pan 36 by the n e raw gs. v framework .31 is an outer sheet metal cover 38 1 15 a transverse vertical sectional i of which forms the outer face of the door.- Between refrigerating h F refrigerating .ap the inner pan 36 and the outer covering 38 ratus embodyi my invention; 1 there is provided a pluralityof insulating units Fig. 2 is a perspec ive ides" of one of .the in- 39. Surrounding the food compartment 21 and sulating units shown within the walls of the the inner liner 33 are the outer sheet metal walls cabinet in Fig. 1;, v I E In which form the outer structure of the cabinet 55 li'ig. 3 is a transversevertical sectional view and which are also fastened to the framework 34 wood 31 or other suitable material having 'alow 45.

but which are spaced from the inner sheet metal walls or inner liner 33. Between the inner liner 33 and the outer sheet metal walls 458 are a plurality of insulating units similar to the insulating units 39 shown within the door structure and also designated by the reference character 39.

Referring now to Figs. 2, I, and 8 for a more complete disclosure of the insulating units 39, there is shown an outer envelope or bag t2 former. of a waterproof paper such as sheet formed of a plurality of sheets of paper having a thin sheet of asphalt therebetween. This bag is sealed by suitable means, such as asphalt, in order to exclude external air and moisture from the insulating unit. Within this bag or waterproof enclosure 52 is a plurality of sheets designated by the reference character 13.

Referring now more paiticularly to Figs. '7 and 8 for a better. disclosure of the sheets, there is shown a sheet of paper M having its opposite side or longitudinal edge portions turned back upon itself and curled to form the tubular structures .5 which are fastened by asphalt as at 46 in order to retain this form. Between the curled tubular edge portions of this sheet there is provided a sheet 47 of a heat reflecting material such as bright aluminum foil which is fastened to the sheet of paper it by a thin layer of asphalt 48. Extending at right angles to the tubular structure there is provided at the end portions of the sheet, as well as at the center portions of the sheets, the tubular structures 50 formed of sheets or strips of heavy paper 5! each of which is turned back upon itself and fastened by asphalt at 52 so,as to form a fiat bottom portion with an integral flange portion 55' extending therefrom. These tubular structures 59 which extend along the edges of the sheets 43 at their ends'and also across the center portion of the sheets, have their flat bottom portions and integral flange portions fastened to the sheets by th n layers of asphalt 54 so as to provide a tubular frame structure which is made a unit with the sheet and which extends around the edges of the sheet and has a tubular stiffening member which extends across the central portion of the sheet.

These sheets. together with their tubular s "uc tures, are stacked together and within the envelope 42 and are held by being tightly packed within this envelope 42. With this type of structure it is possible to curl andfasten the edges as well as apply the foil to the paper in a continuous machine and the transverse tubular structures may be fastened to the sheets on top of hn; foil as the material leaves or is drawn from the machine. In thisway the structure may be very rapidly and economically ,manufactured. The only material required is heavy paper, aluminum foil, asphalt, and a waterproof envelope. By manufacturing this insulating structure in this manner, its cost may be materially reduced.

Referring nowto Fig. 3, there is disclosed a refrigerator cabinet 69 having an inner liner 6| formed of sheet metal which encloses a food compartment 62 for containing a cooling unit 63 for cooling the food compartment. The front of a food compartment is closed-by a door 64 which is provided with an inner sheet metal member 65 and an outer sheet metal member 66 between which are provided a plurality of relatively small insulating units 61 of a standard size. Surrounding the inner sheet metal liner 6| but spaced therefrom are the outer sheet metal walls 68 Between the inner sheet metal liner or inner wall 6! of the cabinet and the outer walls 68, there is provided the standard insulating units 61 similar to the insulating unit 61 shown within the door. These insulating units 61 are preferably made of a standard size in the shape of a large brick so that they may be turned in one way or another in order to fit the insulating space. In this form, insulating units are all made of the same size to facilitate manufacture and the necessity for a number of different sizes of insulating structures is avoided.

Referring now moreparticularly to Fig. 4, for the details of the insulating units 61, there is shown a sealed envelope or waterproof enclosure 69, which contains a plurality of sheets 10 each of which have the four'edges thereof turned back upon itself and curled so as to form tubular structures generally designated by the reference character H. I

Referring now more particularly to Fig. 9, there is shown a section through one of these tubular structures showing the sheet 10 formed of a sheet of heavy paper 13 to which is fastened by asphalt or other adhesive a sheet of bright metallic foil 74 which, differently from the modification shown in Figs. 1 and 2, extends coextensively with the sheet of paper 13. The edges of this sheet so assembled are turned back upon itself and curled and fastened byasphalt 15 to another portion of the sheet spaced from the edge to form the pernlilanent tubular structures II at the edges of the s eet.

In Fig. 10 there is shown a modified form in which within the enclosure or envelope 8!) there is provided sheets 8| formed of heavy paper 82 having-a sheet of foil 83 fastened thereto and extending co-extensively therewith. The edges of each of the sheets are turned back upon the sheet and curled more than a single revolution in order to form relatively-stifi tubular structures 84 at the edges of the sheets. By reason of the thickness and stiffness of the sheets, particularly because of the asphalt or other adhesive between the sheets, this tubular structure retains its tubular form and when placed within the water-proof envelope or bag 89 is further prevented from unwinding by being tightly confined therein.

Referring now more particularly to Fig. 5, there is shown a modification of the insulating structures shown in Figs. 1 and 2. which modification is generally designated by the reference character '90. In this modification a sealed outer envelope 9| of waterproof paper, or other suitable material, is provided. Packed tightly within this envelope is a plurality of sheet and frame structures 92 having a framework 93 formed of relatively narrow strips of paper 94 turned back upon themselves and" fastened by asphalt 95 in I order to form generally tubular structures with flat bottoms and integral flange portions. These tubular structures with the flat bottoms are preferably fastened to a. sheet of bright alum num heat reflecting foil 96 by a suitable adhesive, such as hot asphalt 91. These tubular structures 93 extend along longitudinal edges of the sheet as well as transversely across the end portions and the center portion of the sheet to form a rigid structure embodying a generally tubular framework fastened to the sheet of foil. The-tubular structures 93 which extend across the end and center portions of the sheet of foil 96 are fastened to the sheet of foil 96 and overlap the projecting flange portions 99 of the tubular structures extending along the side portions of the sheets and fastened thereto by a suitable adhesive such as asphalt, generally designated by the reference character 98.

With this structure the tubular paper framework is provided only at the edge portions of the heat reflecting sheet so that both sides of the heat reflecting sheet are left uncovered in order to reduce the amount of paper required and to get the benefit of the reflecting properties of both sidesof the sheet of foil. .If desired, the alternate sheets of foil may be replaced by paper sheets in order to reduce the cost. This permits each air space to have one heat reflecting surface to reduce radiation. By having the transverse tubular members fastened to the flange portion 99 of the side tubular members a very rigid tubular frame structure is provided. These sheets and frame structures are stacked on top of one another and tightly packed within the envelope so that the sheets are held between the tubular structures and each reinforces the other. The light tubular frames which are formed of paper prevent any substantial amount of heat leakage by direct conduction from one of the foil sheets to the other and in this way increase the efficiency of the foil type of insulation. .This construction also reduces the weight of the insulation and thereby permits a reduction in the weight of the .cabinet which renders it more easily movable.

This form may also be readily manufactured automatically by a suitable machine wherein the tubular structures are formed automatically and are fastened by the machine to the foil at a rapid rate. The tubular sections are resilient and compressible and in order to obtain a closer spacing of the sheets to lit the insulation space the entire unit' may be compressed. In this way a single condition and for resiliently spacing said'sheet standard tubular section may be used for different thicknesses of air spaces and insulation spaces. In this way I have provided a refrigerator and insulation therefor which is more eflicient, lighter in weight, and lower in cost.

While the form or embodiment of the invention as herein disclosed constitutes a preferred form, it is 'to be' understood that other forms might be adopted, all coming within the scope .of the claims which follow.

What is claimed is as follows:

1. An insulating structure including a plurality ofslab-like members each formed of a polygon shaped sheet portionhaving a plurality of edge portions forming its perimeter, each of I the edge portions forming the perimeter of said polygon sheet portion being provided with a tubular structure extending along and adjacent it, the axes of each of said tubular structures extending along and parallel to the adjacent edge portion of the perimeter, a plurality of said slablike members being stacked one upon the other and grouped together to form an insulating unit.

2. An insulating structure including slab-like members each formed of a polygon shaped sheet portion having a plurality of edge portions forming its perimeter, a tubular structure for each of said edge portions, each of said tubular structures extending along and having its axis parallel to its adjacent edge portion, the axes of all said tubular structures being located upon one side of the plane of its sheet portion, a plurality of said slab-like members being grouped together to form an insulating unit.

3. An insulating element of the kind described comprising a rectangular sheet of highly flexible material, single hollow elastic members extending lengthwise of the respective edges of vsaid sheet in upright relation to a surface thereof to constitute an elastic frame for'resiliently spacing said sheet from an adjacent sheet to form a dead air space bounded by said frame, and flanges forming parts of said members whereby the latter are secured directly to said surface of said sheet.

4. An insulating element of the kind described comprising a rectangular unitary sheet of flexible material, single hollow elastic members secured to a surface of said sheet and extending along opposite end edges thereof, and additional single hollow elastic members secured to said surface of the sheet and extending along opposite longitudinal edges thereof between and in engagement with said first named hollow members, said hollow members together constituting an elastic rectangular frame in perpendicular relation to said sheet for maintaining the latter in a flat from an adjacent element to form a dead air space bounded by said frame.

5. An insulating element comprising a polygonal sheet of material, some of the edge portions of the polygonal sheet being formed to provide single hollow spacing formations extending lengthwise along some edges of the sheet in upright relation with respect to the surface of said sheet to constitute spacing means for spacing said sheet from an adjacent sheet.

6. An insulating element comprising a polygonal sheet of material, some of the edge portions of the polygonal sheet being turned back uponthe sheet and fastened to the sheet, said turned back portion having such a shape as to form hollow generally tubular spacing formations extending 

